After hosting a Christmas party for military families at Kensington Palace, Prince William and Kate Middleton made their way to Queen Elizabeth II's annual Diplomatic Reception. For the celebrations, Kate wore a stunning tiara called the Lover's Knot that belonged to Princess Diana. Kate looked like Disney's Cinderella in a baby blue bespoke Jenny Packham gown featuring sheer cap sleeves and sparkly sequin accents. She accessorized her gorgeous gown with Diana's Collingwood pearl earrings, which she has worn before. Read on to take a look at her ensemble.